KALISPELL — Wildlife officials say a field assistant on a government grizzly bear study suffered serious injuries when she was attacked by a bear while working in a remote northwestern Montana mountain range.

Montana Fish Wildlife and Parks described the Thursday morning attack as a "surprise defensive encounter" in the Cabinet Mountains south of Libby.

The victim was taken by air ambulance to a Kalispell hospital. Her condition on Friday was unknown and her name was not released.

Officials say she's a field assistant on a U.S. Fish and Wildlife Service grizzly bear project.

Fish Wildlife and Parks spokesman Dillon Tabish says the victim was working at the time of the attack. He declined to say if she was alone or give any other details on what happened, citing an ongoing investigation.